Dental Amalgam

Question 1

Is amalgam a brittle material?

Answer 1

yes

Question 2

Where is amalgam weakest?

Answer 2

tension

Question 3

What happens if you increase gamma2?

Answer 3

weaker material

Question 4

What happens to strength is you add high copper and spherical alloys?

Answer 4

higher early compressive and tensile strength

Question 5

Since amalgam is a metal, what is the effect of thermal cycling?

Answer 5

microleakage

fracture tooth tissue

thermal trauma to pulp

Question 6

How does the amalgam set?

Answer 6

crystal expansion

Question 7

Why does crystal expansion occur?

Answer 7

because the gamma1 (silver/mercury) crystals expand by growth

Question 8

What are the 3 choices of working time?

Answer 8

fast

regular

slow set

Question 9

when would you use fast set?

Answer 9

same appointment cast preparation

Question 10

When would you use silver amalgam?

Answer 10

class I and II cavities

cores for cast restoration

Question 11

What is the minimum cavity depth for amalgam?

Answer 11

2mm

Question 12

What is retention form?

Answer 12

resistance to displacement in an axial direction

Question 13

What is resistance form?

Answer 13

resistance to displacement in any other direction (not axial)

Question 14

How to remove amalgam?

Answer 14

cut a cross

Question 15

How can you retain dental amalgam?

Answer 15

use adhesive (bonding) - conserve tooth tissue

Question 16

What are the benefits of bonging?

Answer 16

increased retention

decreased microleakage

decreased pulpal trauma and inflammation

decreased post-operative sensitivity

decreased incidence of recurrent caries

decreased cuspal deflection

increased fracture resistance pf the tooth

bonding tooth segments together in the treatment of cracked cusp

Question 17

What adhesives do we use?

Answer 17

resin based composite adhesive

• dual (probs this one)
• chemical cure

Question 18

What is the dual cure resin based composite used in the IoD?

Answer 18

nexus 3 (kerr hawe)